I must admit, some years back flying to cairns from melbourne, my backage was interferred with and certain personal belongings went missing.
I was pretty gullible then, but learnt from the experience.
Travel light, to these countries, lock/tape your bags, and use the security facilities at the airports as mentioned. That way at least you have witness's to the state of your baggage prior to leaving.
May even be advantageous to photograph/video your luggage at the airport in some recognisable position, perhaps in front of the departures board if possible. On the tape show how the bags have been locked and personally taped.
